The present disclosure generally relates to head-mounted displays, and specifically relates to active alignment of elements within a head-mounted display.
A head-mounted display (HMD) may be part of a virtual, augmented, or mixed reality system. The HMD typically provides multiple forms of sensory output, such as a video (e.g., via a display) and audio (e.g., via headphones), which operate together to create the illusion that a user is immersed in a virtual world. Such HMDs include a display that provides images to the user. Some HMDs may also include additional optical elements which alter light from the display. Because it is preferable for a HMD to be compact, the geometry between a user's eye, the display, and additional optical elements should generally be precise to prevent distortion of the image viewed by the user. Thus, to prevent HMDs from producing distorted images, the manufacturing process for HMDs should generally ensure the precise alignment of the display and other optical elements in the HMD.
Conventionally, the alignment of the display and other optical elements is accomplished with passive alignment. For example, a display and a reciprocal coupling mechanism of a frame of a HMD may be manufactured with precise mechanical tolerances so that that the display and a frame of the HMD fit together precisely. Although passive alignment may be sufficiently precise to insure adequate quality control, manufacturing the elements of the HMD with the mechanical tolerances required to ensure proper alignment may be prohibitively expensive. Furthermore, a manufacturing process that requires precise machine tolerances may be relatively vulnerable to disruptions in the supply chain. For example, it may not be possible to transition to manufacturing HMDs with a slightly different type of display without entirely reworking the manufacturing process of the other elements of the HMDs.